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s PUBLIC PARTICIPATION NOTIFICATION Site Description The proposed project is located on the Nelson Ready-Mix property(APN#261-020-14) at 22700 State Highway 99, Ripon (San Joaquin County), California. The site is immediately south of the southbound lanes of State Highway 99 and immediately east of the Jack Tone Road over-crossing. The property is owned by Russel C. and Marian F. Nelson of 24389 South Austin Road, Ripon, California. Pro e�ct Objective The objective of the proposed project is to remove the maximum volume of impacted soil and groundwater from the vicinity of a former 4,000-gallon underground diesel storage tank(UST), without encroaching on the Caltrans right-of-way. Soil and groundwater in the vicinity of this former UST has been impacted by petroleum hydrocarbons, primarily diesel. Project Processes To remove the maximum volume of heavily impacted soil from the vicinity of the former UST without Caltrans encroachment,the proposed excavation will be shored. Approximately 50 feet of shoring will be installed along the property line between the former UST and Caltrans right-of-way. The proposed excavation is a rectangular area measuring approximately 50 feet by 20 feet by 18 feet deep. Given that groundwater is present beneath the site at approximately 14 feet bgs, the proposed excavation includes the removal of up to four feet of potentially saturated soil. To maximize the depth of excavation and to remove petroleum hydrocarbons on the groundwater surface, groundwater will be pumped from the excavation. All of the pumped groundwater will be contained in a rented water storage tank. Upon completion of the de-watering operation,the contained groundwater will be treated with granular activated carbon, sampled and discharged to the local sewer system. Once excavation and de-watering operations are complete,the excavation will be backfilled. Once the excavation has been backfilled, the shoring will be remover!. The surface will be finished with a thin layer of aggregate base rock. No asphalt or concrete pavement will be applied. Waste soil generated by the project may be temporarily stockpiled on site and then either disposed of off-site or re-used. Potential Hazards Potential hazards associated with the proposed project include those normally associated with excavation operations and possible exposure to petroleum hydrocarbons. The property is an active cement mixing plant and is completely enclosed by fencing and lockable gates. The proposed excavation is located entirely on private property. It will not be readily visible from the street and will not be near any expected foot traffic. Heavy equipment operation will be limited to the property, except for possible truck traffic. The primary contaminant of concern is diesel. Volatile organic compounds have not been detected in significant concentrations. As such, possible inhalation and/or dermal exposure to hazardous concentrations of petroleum hydrocarbons are not considered significant.